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Title: PD-MORL: Preference-Driven Multi-Objective Reinforcement Learning Algorithm
Multi-objective reinforcement learning (MORL) approaches have emerged to tackle many real-world problems with multiple conflicting objectives by maximizing a joint objective function weighted by a preference vector. These approaches find fixed customized policies corresponding to preference vectors specified during training. However, the design constraints and objectives typically change dynamically in real-life scenarios. Furthermore, storing a policy for each potential preference is not scalable. Hence, obtaining a set of Pareto front solutions for the entire preference space in a given domain with a single training is critical. To this end, we propose a novel MORL algorithm that trains a single universal network to cover the entire preference space scalable to continuous robotic tasks. The proposed approach, Preference-Driven MORL (PD-MORL), utilizes the preferences as guidance to update the network parameters. It also employs a novel parallelization approach to increase sample efficiency. We show that PD-MORL achieves up to 25% larger hypervolume for challenging continuous control tasks and uses an order of magnitude fewer trainable parameters compared to prior approaches.  more » « less
Award ID(s):
1651624
PAR ID:
10537847
Author(s) / Creator(s):
; ;
Publisher / Repository:
The Eleventh International Conference on Learning Representations, https://openreview.net/forum?id=zS9sRyaPFlJ
Date Published:
Subject(s) / Keyword(s):
Machine Learning (cs.LG) Artificial Intelligence (cs.AI)
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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